1. Disseminated neoplasia in cultured Crassostrea gasar oysters from northeast Brazil
- Author
-
Philippe Soudant, Fernando Ramos Queiroga, Patricia Mirella da Silva, Hélène Hégaret, Natanael Dantas Farias, Universidade Federal da Paraiba (UFPB), Laboratoire des Sciences de l'Environnement Marin (LEMAR) (LEMAR), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), and ANR-10-LABX-0019,LabexMER,LabexMER Marine Excellence Research: a changing ocean(2010)
- Subjects
0301 basic medicine ,Gill ,Oyster ,Veterinary medicine ,Histology ,animal structures ,Population level ,Northeast brazil ,[SDV.BC]Life Sciences [q-bio]/Cellular Biology ,Flow cytometry ,03 medical and health sciences ,Phagocytosis ,biology.animal ,Hemolymph ,Prevalence ,medicine ,Animals ,Population assessment ,14. Life underwater ,Crassostrea ,Crassostrea gasar ,Ecology, Evolution, Behavior and Systematics ,Shellfish ,[SDV.EE]Life Sciences [q-bio]/Ecology, environment ,biology ,medicine.diagnostic_test ,ACL ,[SDV.BA]Life Sciences [q-bio]/Animal biology ,04 agricultural and veterinary sciences ,Haemocytic leukemia ,030104 developmental biology ,040102 fisheries ,0401 agriculture, forestry, and fisheries ,[SDE.BE]Environmental Sciences/Biodiversity and Ecology ,Reactive oxygen species ,Brazil - Abstract
International audience; Disseminated neoplasia (DN) is a disease that affects bivalves worldwide and can lead to mass mortalities. In the present study, a pathological survey conducted from December 2011 to August 2012 in Crassostrea gasar, an oyster of commercial interest in northeast Brazil, revealed the occurrence of DN in oysters reared in the Mamanguape estuary, Paraiba State, Brazil. The present work describes the pathological and functional aspects of the disease in C. gasar by light microscopy (haemolymph cell monolayer and histological section) and flow cytometry analyses. The prevalence of the disease was low (7.1% of 182 oysters examined). Enlarged (neoplastic) cells showed reniform, ovoid or circular-shaped nuclei, with prominent nucleoli and predominantly short filipodia. They were found in the haemolymph and infiltrated the connective tissues of different organs, including the digestive system, gills and gonads, as well as in the sinuses and vessels. Three levels of progression of DN in tissues were observed, light (61.5%), moderate (15.4%) and advanced (23.1%). The viability of neoplastic cells circulating in the haemolymph (97.4%) was similar to that in the haemocytes (95.7%). The neoplastic cells showed low phagocytic ability (3.9%) compared with that of haemocytes (42.4%). Conversely, reactive oxygen species production (679 A.U.) and the total haemocyte count (3.9 x 10(6) cells mL(-1)) were higher in the affected oysters than in unaffected oysters (268 A.U. and 1.5 x 10(6) cells mL(-1), respectively). The low prevalence and primarily mild intensity found in the sampled oysters does not preclude an impact at the population level. A timely survey of DN is thus recommended in order to assess the severity and impact of this disease in wild and cultured populations of C. gasar oysters.
- Published
- 2018
- Full Text
- View/download PDF